Various industries require that materials be mixed prior to usage. For example, dentists often need to prepare hardenable construction materials for making impressions of the teeth and other portions of the mouth for study and treatment. Dentists prepare a hydrophilic impression material, such as alginate, for use in making the impression. The alginate is supplied in a powdered form and water is added by the dentist or dental assistant to prepare the material for use. Once the water is added and the ingredients are mixed together, the alginate sets quickly, such as within about 30-90 seconds from the time the water is added. Before the alginate sets, the alginate is typically placed on a tray and then the alginate is positioned against the portion of the mouth desired for making the impression. Once the alginate sufficiently sets in the position against the mouth, the alginate forms a hardened structure containing a reverse image impression of the portion of the mouth.
From this alginate impression, the dentists will often make an actual model or mold of the mouth parts by molding from the alginate impression. Another material called "stone", more rigid than alginate, may be utilized for making the mold. Like alginate, stone is supplied in a powdered form, water is added, and then the materials are mixed together and positioned around the impression in the alginate. Once the stone sets, the alginate impression is removed and the stone mold is finished.
Various methods of mixing alginate and/or stone are known. One method utilizes a rubber bowl and a spatula for mixing the powder and the water manually. This method is awkward and takes a high amount of skill to correctly mix the ingredients before the materials set and without producing excessively large air bubbles, which can cause defects in the impression of mold. For alginate, the mixed material must then be manually scooped from the bowl with the spatula to the tray in the appropriate amount for insertion into the mouth for holding the alginate against the desired portion of the mouth. Further, the bowl and the spatula must be cleaned afterwards and disinfected before subsequent reuse.
Another method of mixing alginate and/or stone is to supply a mechanism for spinning a bowl while the operator manually manipulates a spatula to mix the materials. This method is messy since the bowl and spatula must be cleaned after use. This method also requires a high amount of skill to appropriately mix the ingredients in a short amount of time before the material sets. Further, these tools must be disinfected prior to subsequent use. In addition, the mechanism for spinning the bowl increases the costs to the dentist.
A further method of mixing the materials utilizes a self-contained mixer for mixing the materials within an enclosed chamber of a rigid container, much like a conventional blender. A spinning blade member rotates to mix the materials within the rigid container. Not only is the mixer costly, but the components must be cleaned after each use and disinfected.
Other industries which utilize mixers and various methods of mixing ingredients include other medical fields, engineering, biology, and art. In many of these industries, materials are mixed for making impressions where the cost, the ease of use, and the quality of the mixed materials are significant concerns. Food preparation is another area where there is a need for properly mixed powdered materials and liquids.
There is a need for mixing bag arrangements and methods for mixing materials which addresses at least some of the above problems and other problems.